1. Field of the Invention
The invention relates to lens modules and more particularly to lens modules with a patterned substrate and fabrication methods thereof.
2. Description of the Related Art
Micro-optical components such as one- and two-dimensional lens assemblies are typically used in devices such as lens modules. The design and manufacturing of lens modules for portable electronic products is extremely challenging. Some challenging factors include: high production volume, constant price erosion, size limitations and changing performance and functionality requirements.
FIG. 1 is a schematic view illustrating a configuration of a conventional imaging lens module. Referring to FIG. 1, a conventional imaging lens module 10 includes a first plano-plano substrate 12 with a first lens 14 and a second lens 16 formed on both sides of the substrate 12, a second plano-plano substrate 22 with a third lens 24 and a fourth lens 26 formed on both sides of the substrate 22, and a spacer 36 interposed between the first and the second substrates 12 and 22. A black yard coating layer 18 can be formed on the second lens 16 to serve as an aperture. An antireflection film 28 can be formed on the fourth lens 26. The spacer 36 can separate the first and the second substrates 12 and 22 by a predetermined gap. Additionally, spacers 34 and 38 are, respectively formed on the front surface of the first substrate 12 and the back surface of the second substrate 22. Stacking glues 32 are used between the spacers 34, 36 and 38 and the first and second substrates 12 and 22.
Conventionally, packaging techniques are used when stacking and aligning the imaging lens module 10. There are some problems associated with the conventional packaged lens module, such as high spacer production costs, limitations of the substrate used therein and inaccurate spacer thicknesses and alignment of the optical center of the lens module due to spacer processes which cause misalignment.